1. Field of the Invention
The present invention relates to a cooling device, and more particularly to a liquid cooling device for rapidly cooling a heat producing component such as a central processing unit (CPU).
2. Description of Related Art
Over the past few years, CPU speeds have been increasing at a dramatic rate. In order to achieve this, CPUs have ever-higher levels of integration, are drawing more power and have higher clock rates. This leads to greater heat being produced by the CPU in the computer. The waste heat can accumulate and generate unacceptable high temperatures and thermal stress in the CPU, resulting in reliability performance degradation and system malfunction. Heat sinks have been added to all modern PC CPUs to help try to dissipate some of the heat from the processor into the surrounding environment, many of these heat sinks also include fans to help dissipate heat, but CPU temperatures have increased to the point where fan cooling is no longer sufficient and liquid cooling is now coming into use.
Liquid cooling essentially acts like a radiator for the CPU inside the computer. A liquid cooling system circulates a liquid through a cooling plate attached to the processor inside the computer. As the liquid passes through the cooling plate, heat is transferred from the hot processor to the cooler liquid. The hot liquid then moves out to a heat sink and transfers heat to the ambient air flowing through the heat sink. The cooled liquid then travels back through the system to the CPU to continue the process.
A liquid cooling device 70 in accordance with related art is shown in FIG. 8. The liquid cooling device 70 generally comprises a pump 72, a cooling plate 74, and a heat sink 76 defining a chamber therein. A zigzagged passageway 762 is defined in the chamber of the heat sink 76 by a plurality of parallel partitions for carrying liquid coolant. The pump 72 defines a first inlet 722 and a first outlet 724 away from the first inlet 722. The cooling plate 74 defines a second inlet 742 and a second outlet 744 connecting with the first inlet 722 of the pump 72. A pipe 77 connects an inlet (not labeled) of the heat sink 76 and the first outlet 724 of the pump 72. An outlet (not labeled) of the heat sink 76 is connected to the second inlet 742 of the cooling plate 74 through another pipe 78. Thus, the heat sink 76, the pump 72 and the cooling plate 74 together form a circuit for transferring heat from a heat producing component (not shown) to the liquid coolant contained in the circuit and for dissipating the heat at the cooling plate 74.
However, there is one key limitation of the liquid cooling device 70 that has prevented its widespread adoption, that is, leakage. The fluid-handling components must all be connected to each other with pipes, resulting in a minimum of six connection joints shown in FIG. 8. That means that the liquid coolant (typically water) that runs through this liquid cooling device 70 has a minimum of six different locations where a leak is possible, not to mention the possibility of leaks occurring somewhere in the pipe itself. More particularly, the cooling plate 74 communicates with the heat sink 76 and the pump 72 via two pipes; thus, two connection joints are formed adjacent to a heat producing component, which is placed under the cooling plate 74. This increases the risk of the heat producing component failure or damage due to leakage. The fear of water leakage in the computer is enough to prevent some users/designers from adopting this technology.
What is needed, therefore, is a liquid cooling device for a heat producing component, which can decrease the possibility of leaks.